可能开发安卓的人大多数都用过很多下拉刷新的开源组件,但是今天用了官方v4支持包的SwipeRefreshLayout觉得效果也蛮不错的,特拿出来分享。
简介:
SwipeRefreshLayout组件只接受一个子组件:即需要刷新的那个组件。它使用一个侦听机制来通知拥有该组件的监听器有刷新事件发生,换句话说我们的Activity必须实现通知的接口。该Activity负责处理事件刷新和刷新相应的视图。一旦监听者接收到该事件,就决定了刷新过程中应处理的地方。如果要展示一个“刷新动画”,它必须调用setRefrshing(true),否则取消动画就调用setRefreshing(false)。
并且这个东西只支持下拉刷新,大家可以自定义View继承它实现你的上拉加载。
怎样使用SwipeRefreshLayout:
使用起来非常简单。
下面将用一个实例展示如何使用官方这个下拉刷新控件,末尾我还模仿虚拟实现了一个小的上拉加载效果,可以供大家向上分析。
先上图:
上点代码:
activity_main.xml
<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context="com.example.nanchen.swiperefreshlayoutdemo.MainActivity"> <android.support.v4.widget.SwipeRefreshLayout android:id="@+id/main_srl" android:layout_width="wrap_content" android:layout_height="wrap_content"> <ListView android:id="@+id/main_lv" android:layout_width="wrap_content" android:layout_height="wrap_content"> </ListView> </android.support.v4.widget.SwipeRefreshLayout></RelativeLayout>
menu_layout.xml
<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <ProgressBar style="?android:attr/progressBarStyleSmall" android:layout_width="wrap_content" android:layout_height="wrap_content" android:id="@+id/progressBar"/> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="正在玩命加载中...." android:id="@+id/textView2"/></LinearLayout>
MainActivity.java
package com.example.nanchen.swiperefreshlayoutdemo;import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.support.v4.widget.SwipeRefreshLayout;import android.support.v7.app.AppCompatActivity;import android.view.View;import android.widget.AbsListView;import android.widget.ArrayAdapter;import android.widget.ListView;import java.util.ArrayList;import java.util.Arrays;import java.util.List; public class MainActivity extends AppCompatActivity implements AbsListView.OnScrollListener { private SwipeRefreshLayout swipeRefreshLayout; private ListView lv; private ArrayAdapter adapter; private List<String> list; private View footerView; private Handler handler = new Handler(){ @Override public void handleMessage(Message msg) { super.handleMessage(msg); switch (msg.what){ case 0x101: if (swipeRefreshLayout.isRefreshing()){ adapter.notifyDataSetChanged(); swipeRefreshLayout.setRefreshing(false);//设置不刷新 } break; } } }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); swipeRefreshLayout = (SwipeRefreshLayout) findViewById(R.id.main_srl); lv = (ListView) findViewById(R.id.main_lv); footerView = getLayoutInflater().inflate(R.layout.loading_layout,null); lv.addFooterView(footerView); lv.setOnScrollListener(this); list = new ArrayList<>(); list.addAll(Arrays.asList("Java","php","C++","C#","IOS","html","C","J2ee","j2se","VB",".net","Http","tcp","udp","www")); adapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1, android.R.id.text1,list); lv.setAdapter(adapter); swipeRefreshLayout.setColorSchemeResources(android.R.color.holo_blue_bright, android.R.color.holo_green_light, android.R.color.holo_orange_light, android.R.color.holo_red_light); swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() { @Override public void onRefresh() { new LoadDataThread().start(); } }); } private int visibleLastIndex;//用来可显示的最后一条数据的索引 @Override public void onScrollStateChanged(AbsListView view, int scrollState) { if(adapter.getCount() == visibleLastIndex && scrollState == SCROLL_STATE_IDLE){ new LoadDataThread().start(); } } @Override public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) { visibleLastIndex = firstVisibleItem + visibleItemCount - 1;//减去最后一个加载中那条 } /** * 模拟加载数据的线程 */ class LoadDataThread extends Thread{ @Override public void run() { initData(); try { Thread.sleep(2000); } catch (InterruptedException e) { e.printStackTrace(); } handler.sendEmptyMessage(0x101);//通过handler发送一个更新数据的标记 } private void initData() { list.addAll(Arrays.asList("Json","XML","UDP","http")); } }}
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持武林网。
新闻热点
疑难解答